OLED display panel and manufacture method thereof

ABSTRACT

The present invention discloses an OLED display panel, comprising a substrate; a photochromic layer, being formed on the substrate, and comprising photochromic material which changes from transparent to opaque under excitation of light; a transparent anode, formed at one side of the photochromic layer away from the substrate; an emission layer, formed at one side of the transparent anode away from the photochromic layer, and employed to emit light, and the light comprises a wavelength employed to excite the photochromic material; and a semitransparent cathode, formed at one side of the emission layer away from the transparent anode, and employed to pass a portion of the light and reflect the other portion of the light. The OLED display panel of the present invention has the longer micro cavity total optical distance. The present invention further discloses a manufacture method of an OLED display panel.

CROSS REFERENCE

This application claims the priority of Chinese Patent Application No.201610205651.3, entitled “OLED display panel and manufacture methodthereof”, filed on Apr. 5, 2016, the disclosure of which is incorporatedherein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to an OLED display panel technical field,and more particularly to an OLED display panel and a manufacture methodof the OLED display panel.

BACKGROUND OF THE INVENTION

The OLED (Organic Light-Emitting Diode) display is a new type displaytechnology developed in the middle of the twenty century, and possessesmany advantages of ultra thin, all solid state, active luminescence,fast response speed, high contrast, no visual restriction, wide worktemperature range, low power consumption, low cost, strong seismiccapacity and possibility of flexible display, and will become the mainstream of the next generation of flat panel display. Because of theexcellent performance and the huge market potential, many factories andscientific research institutions in the worldwide have invested in theproduction and research of the OLED display panel.

However, due to the vibration tape and the inhomogeneous broadeningeffect, either for the organic small molecules or high polymerluminescent material, the spectral halfwidth is generally larger than 80nm. Therefore, the usage ratio is very low in the color displaymanufactured with synthesis of the red, green, blue, three primarycolors. For manufacturing the OLED display panel with narrow-lineemission, people change the structure of the OLED display panel, andmanufacture the Fabry-Perot (F-P) optical micro cavity of the OLEDdisplay panel to acquire the high brightness narrow-line emission. Theoptical micro cavity does not only realize the narrow-line emission butalso significantly enhance the intensity of emission relative to theelement of micro cavity structure. The regular F-P optical micro cavitystructure requires two reflective mirror surfaces, which generallyemploy metal-metal structure. Therefore, the micro cavity total opticaldistance of the F-P optical micro cavity structure is restricted by thethickness and refractivity of the organic film layer in the OLED displaypanel, and the micro cavity total optical distance is shorter. It isdifficult for the insiders to increase the micro cavity total opticaldistance by adjusting the organic film layer in the OLED display panel.

SUMMARY OF THE INVENTION

An objective of the present invention is to provide an OLED displaypanel, which has the longer micro cavity total optical distance, and amanufacture method of the OLED display panel.

For realizing the aforesaid objective, the technical solution utilizedby the embodiments of the present invention is:

On one hand, provided is an OLED display panel, comprising:

a substrate;

a photochromic layer, being formed on the substrate, and comprisingphotochromic material which changes from transparent to opaque underexcitation of light;

a transparent anode, formed at one side of the photochromic layer awayfrom the substrate;

an emission layer, formed at one side of the transparent anode away fromthe photochromic layer, and employed to emit light, and the lightcomprises a wavelength employed to excite the photochromic material; and

a semitransparent cathode, formed at one side of the emission layer awayfrom the transparent anode, and employed to pass a portion of the lightand reflect the other portion of the light.

The transparent anode employs tin indium oxide material.

The semitransparent cathode employs magnesium-silver alloy.

As the emission layer does not emit the light, a transmissivity of thephotochromic layer in the visible light range is larger than 90%; as theemission layer emits the light, the transmissivity of the photochromiclayer in the visible light range is smaller than 10%.

The photochromic material comprises one or more of silver halide, zinchalide, copper halide, magnesium halide, spiro pyran, phenoxazine,oxazine dye and pyridine.

The OLED display panel further comprises an adjustment layer formedbetween the photochromic layer and the transparent anode, and theadjustment layer employs transparent material, and is employed to adjusta gap between the photochromic layer and the transparent anode.

The OLED display panel further comprises:

a Hole Injection Layer, formed at the one side of the transparent anodeaway from the photochromic layer;

a Hole Transporting Layer, formed between the Hole Injection Layer andthe emission layer;

an Electron Transport Layer, formed at one side of the emission layeraway from the Hole Transporting Layer; and

an Electron Injection Layer formed between the Electron Transport Layerand the semitransparent cathode.

On the other hand, further provided is a manufacture method of an OLEDdisplay panel, comprising:

forming a photochromic layer on the substrate, and the photochromiclayer comprises photochromic material which changes from transparent toopaque under excitation of light;

sequentially forming a transparent anode, an emission layer and asemitransparent cathode at one side of the photochromic layer away fromthe substrate, and the emission layer is employed to emit light, and thelight comprises a wavelength employed to excite the photochromicmaterial.

The step of forming the photochromic layer on the substrate comprises:

cleaning the substrate;

depositing the photochromic material on the substrate with evaporation,sputtering or electron beam to form the photochromic layer.

The step of sequentially forming a transparent anode, an emission layerand a semitransparent cathode at one side of the photochromic layer awayfrom the substrate comprises:

depositing tin indium oxide material at one side of the photochromiclayer away from the substrate with evaporation to form the transparentanode;

depositing emission material at one side of the transparent anode awayfrom the photochromic layer with evaporation to form the emission layer;and

depositing magnesium-silver alloy at one side of the emission layer awayfrom the transparent anode to form the semitransparent cathode.

Compared with prior art, the present invention possesses benefits below:

In the OLED display panel according to the embodiment of the presentinvention, the substrate, the photochromic layer, the transparent anode,the emission layer and the semitransparent cathode are sequentiallystacked up. As the emission layer emits the light, the photochromiclayer becomes opaque with excitation of the light, and thus to form theresonant cavity with the semitransparent cathode. Because thephotochromic layer is at the one side of the transparent anode away fromthe emission layer, the thickness of the photochromic layer will notinfluence the voltage drop and the electrical property of the OLEDdisplay panel, and meanwhile, the micro cavity total optical distance isincreased prevent the overdependency of the micro cavity adjustment tothe organic film layer (such as the emission layer) of the OLED displaypanel for raising the adjustable performance of the OLED display paneland making the OLED display panel possess high light efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the presentinvention, the following figures will be described in the embodimentsare briefly introduced. It is obvious that the drawings are only someembodiments of the present invention, those of ordinary skill in thisfield can obtain other figures according to these figures without payingthe premise.

FIG. 1 is a structure diagram of an OLED display panel provided by theembodiment of the present invention.

FIG. 2 is a flowchart of a manufacture method of an OLED display panelprovided by the embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Embodiments of the present invention are described in detail with thetechnical matters, structural features, achieved objects, and effectswith reference to the accompanying drawings as follows. It is clear thatthe described embodiments are part of embodiments of the presentinvention, but not all embodiments. Based on the embodiments of thepresent invention, all other embodiments to those of ordinary skill inthe premise of no creative efforts obtained, should be considered withinthe scope of protection of the present invention.

Please refer to FIG. 1. The embodiment of the present invention providesan OLED (Organic Light-Emitting Diode) display panel, comprising asubstrate 1, a photochromic layer 2, a transparent anode 3 (Anode), anemission layer 6 (Emitting Material Layer) and a semitransparent cathode9 (Cathode). The photochromic layer 2 is being formed on the substrate1, and the photochromic layer 2 comprises photochromic material whichchanges from transparent to opaque under excitation of light. Namely, asthe photochromic layer 2 is excited by the light, the photochromic layer2 is opaque to reflect the light. The transparent anode 3 is formed atone side of the photochromic layer 2 away from the substrate 1, and isemployed to pass the light. The emission layer 6 is formed at one sideof the transparent anode 3 away from the photochromic layer 2, and isemployed to emit light, and the light comprises a wavelength employed toexcite the photochromic material. The semitransparent cathode 9 isformed at one side of the emission layer 6 away from the transparentanode 3, and is employed to pass a portion of the light and reflect theother portion of the light.

In this embodiment, the substrate 1, the photochromic layer 2, thetransparent anode 3, the emission layer 6 and the semitransparentcathode 9 are sequentially stacked up. As the emission layer 6 emits thelight, the photochromic layer 2 becomes opaque with excitation of thelight, and thus to form the resonant cavity with the semitransparentcathode 9. Because the photochromic layer 2 is at the one side of thetransparent anode 3 away from the emission layer 6, the thickness of thephotochromic layer 2 will not influence the voltage drop and theelectrical property of the OLED display panel, and meanwhile, the microcavity total optical distance is increased prevent the overdependency ofthe micro cavity adjustment to the organic film layer (such as theemission layer 6) of the OLED display panel for raising the adjustableperformance of the OLED display panel and making the OLED display panelpossess high light efficiency.

It should be understood that the photochromic material can be depositedon the substrate 1 with evaporation, sputtering or electron beam to formthe photochromic layer 2.

Furthermore, as being a possible embodiment, the transparent anode 3employs Indium Tin Oxide (ITO) material, and can raise the HoleInjection ability, and reduce the Hole Injection energy barrier. Itshould be understood that in other embodiments, the transparent anode 3also can employ other conductive materials with high work function.

Furthermore, as being a possible embodiment, the semitransparent cathode9 employs magnesium-silver (Mg/Ag) alloy. The ratio of magnesium andsilver is 1:9. It should be understood that in other embodiments, thetransparent anode 3 also can employ other semitransparent conductivematerials with low work function.

Furthermore, as being a possible embodiment, as the emission layer 6does not emit the light, a transmissivity of the photochromic layer 2 inthe visible light range is larger than 90%; as the emission layer 6emits the light, the transmissivity of the photochromic layer 2 in thevisible light range is smaller than 10%. Preferably, under theexcitation of the light, the transmissivity of the photochromic layer 2in the visible light range is changed from 100% to 0%.

Selectably, the photochromic layer 2 can comprise organic photochromicmaterial and/or inorganic photochromic material. As an illustration, thephotochromic material comprises one or more of silver halide, zinchalide, copper halide, magnesium halide, spiro pyran, phenoxazine,oxazine dye and pyridine. The base material of the photochromic layer 2is selected from but not limited to silicon dioxide or organic resin,and the doping amount of the photochromic material is 0.011 wt %-10 wt%.

Furthermore, as being a possible embodiment, referring to FIG. 1, theOLED display panel further comprises an adjustment layer 10 formedbetween the photochromic layer 2 and the transparent anode 3, and theadjustment layer 10 employs transparent material, and is employed toadjust a gap between the photochromic layer 2 and the transparent anode3, and thus to increase the micro cavity total optical distance inadvance for raising the adjustable performance of the OLED displaypanel.

Furthermore, as being a possible embodiment, referring to FIG. 1, theOLED display panel further comprises a Hole Inject Layer 4 (HIL), a HoleTransport Layer 5 (HTL), an Electron Transport Layer 7 (ETL) and anElectron Inject Layer 8 (EIL), which are employed to increases thetransportation and the balance of electron and hole, and thus to promotethe light efficiency of the OLED display panel. The Hole Injection Layer4 is formed at the one side of the transparent anode 3 away from thephotochromic layer 2. The Hole Transporting Layer 5 is formed betweenthe Hole Injection Layer 4 and the emission layer 6. The ElectronTransport Layer 7 is formed at one side of the emission layer 6 awayfrom the Hole Transporting Layer 5. The Electron Injection Layer 8 isformed between the Electron Transport Layer 7 and the semitransparentcathode 9.

Furthermore, as being a possible embodiment, the substrate 1 is aflexible substrate, and then the OLED is a flexible display panel, whichcan be applied for more usage environment, and the application is wideand various. Certainly, in other embodiment, the substrate 1 also can bea hard substrate, or a combination of a flexible substrate and a hardsubstrate.

Please refer to FIG. 1 and FIG. 2. The embodiment of the presentinvention further provides a manufacture method of an OLED displaypanel, comprising:

Step 1: forming a photochromic layer 2 on the substrate 1, and thephotochromic layer 2 comprises photochromic material which changes fromtransparent to opaque under excitation of light;

Step 2: sequentially forming a transparent anode 3, an emission layer 6and a semitransparent cathode 9 at one side of the photochromic layer 2away from the substrate 1, and the emission layer 6 is employed to emitlight, and the light comprises a wavelength employed to excite thephotochromic material.

With the OLED display panel formed by the manufacture method of theembodiment, the substrate 1, the photochromic layer 2, the transparentanode 3, the emission layer 6 and the semitransparent cathode 9 aresequentially stacked up. As the emission layer 6 emits the light, thephotochromic layer 2 becomes opaque with excitation of the light, andthus to form the resonant cavity with the semitransparent cathode 9.Because the photochromic layer 2 is a t the one side of the transparentanode 3 away from the emission layer 6, the thickness of thephotochromic layer 2 will not influence the voltage drop and theelectrical property of the OLED display panel, and meanwhile, the microcavity total optical distance is increased prevent the overdependency ofthe micro cavity adjustment to the organic film layer (such as theemission layer 6) of the OLED display panel for raising the adjustableperformance of the OLED display panel and making the OLED display panelpossess high light efficiency.

Furthermore, as being a possible embodiment, the Step 1 comprises:

Step 11: cleaning the substrate 1;

Step 12: depositing the photochromic material on the substrate 1 withevaporation, sputtering or electron beam to form the photochromic layer2.

The evaporation means the process that the material to be film (such asphotochromic material) is positioned in vacuum for evaporation orsublimation to be separated out on the surface of the substrate 1. Thesputtering means that the particles (ion or neutral atom, molecule, suchas photochromic material) with certain energy bombards the solid surfaceto make the atoms or molecules close to the surface of the solid gainthe enough energy, and ultimately escape away from the solid surface.

Furthermore, as being a possible embodiment, the Step 2 comprises:

Step 21: depositing tin indium oxide material at one side of thephotochromic layer 2 away from the substrate 1 with evaporation to formthe transparent anode 3;

Step 22: depositing emission material at one side of the transparentanode 3 away from the photochromic layer 2 with evaporation to form theemission layer 6; and

Step 23: depositing magnesium-silver alloy at one side of the emissionlayer 6 away from the transparent anode 3 to form the semitransparentcathode 9.

The transparent anode 3 employs Indium Tin Oxide (ITO) material, and canraise the Hole Injection ability, and reduce the Hole Injection energybarrier.

The detail description has been introduced above for the embodiment ofthe invention. Herein, a specific case is applied in this article forexplain the principles and specific embodiments of the present inventionhave been set forth. The description of the aforesaid embodiments isonly used to help understand the method of the present invention and thecore idea thereof; meanwhile, for those of ordinary skill in the art,according to the idea of the present invention, there should be changeseither in the specific embodiments and applications but in sum, thecontents of the specification should not be limitation to the presentinvention.

What is claimed is:
 1. An OLED display panel, comprising: a substrate; aphotochromic layer, being formed on the substrate, and comprisingphotochromic material which changes from transparent to opaque underexcitation of light; a transparent anode, formed at one side of thephotochromic layer away from the substrate; an emission layer, formed atone side of the transparent anode away from the photochromic layer, andemployed to emit light, and the light comprises a wavelength employed toexcite the photochromic material; and a semitransparent cathode, formedat one side of the emission layer away from the transparent anode, andemployed to pass a portion of the light and reflect the other portion ofthe light.
 2. The OLED display panel according to claim 1, wherein thetransparent anode employs tin indium oxide material.
 3. The OLED displaypanel according to claim 1, wherein the semitransparent cathode employsmagnesium-silver alloy.
 4. The OLED display panel according to claim 1,wherein as the emission layer does not emit the light, a transmissivityof the photochromic layer in the visible light range is larger than 90%;as the emission layer emits the light, the transmissivity of thephotochromic layer in the visible light range is smaller than 10%. 5.The OLED display panel according to claim 4, wherein the photochromicmaterial comprises one or more of silver halide, zinc halide, copperhalide, magnesium halide, spiro pyran, phenoxazine, oxazine dye andpyridine.
 6. The OLED display panel according to claim 1, wherein theOLED display panel further comprises an adjustment layer formed betweenthe photochromic layer and the transparent anode, and the adjustmentlayer employs transparent material, and is employed to adjust a gapbetween the photochromic layer and the transparent anode.
 7. The OLEDdisplay panel according to claim 1, wherein the OLED display panelfurther comprises: a Hole Injection Layer, formed at the one side of thetransparent anode away from the photochromic layer; a Hole TransportingLayer, formed between the Hole Injection Layer and the emission layer;an Electron Transport Layer, formed at one side of the emission layeraway from the Hole Transporting Layer; and an Electron Injection Layerformed between the Electron Transport Layer and the semitransparentcathode.
 8. A manufacture method of an OLED display panel, comprisingsteps of: forming a photochromic layer on the substrate, and thephotochromic layer comprises photochromic material which changes fromtransparent to opaque under excitation of light; sequentially forming atransparent anode, an emission layer and a semitransparent cathode atone side of the photochromic layer away from the substrate, and theemission layer is employed to emit light, and the light comprises awavelength employed to excite the photochromic material.
 9. Themanufacture method of the OLED display panel according to claim 8,wherein the step of forming the photochromic layer on the substratecomprises: cleaning the substrate; depositing the photochromic materialon the substrate with evaporation, sputtering or electron beam to formthe photochromic layer.
 10. The manufacture method of the OLED displaypanel according to claim 9, wherein the step of sequentially forming atransparent anode, an emission layer and a semitransparent cathode atone side of the photochromic layer away from the substrate comprises:depositing tin indium oxide material at one side of the photochromiclayer away from the substrate with evaporation to form the transparentanode; depositing emission material at one side of the transparent anodeaway from the photochromic layer with evaporation to form the emissionlayer; and depositing magnesium-silver alloy at one side of the emissionlayer away from the transparent anode to form the semitransparentcathode.